Many people know that exercise can strengthen the body and slow down the aging process, but what is the reason for it? German researchers have found that the reason may be hidden in the white blood cells. Exercise can keep the body’s immune system “young”, which in turn slows down the aging of the body. Telomeres are longer Researchers have found that a segment of deoxyribonucleic acid (DNA) at the end of a chromosome in the white blood cells of long-distance runners is longer than that of the average healthy adult. The length of this DNA sequence, called “telomeres,” is associated with aging in humans. Emmanuel Scodarakos, a geneticist at the Wistar Institute in Philadelphia, explained that telomeres act similarly to the plastic head at the end of a shoelace. The plastic head prevents the laces from fraying, while the telomeres protect the chromosomes from damage. Cells divide continuously throughout their lives, Skordalakos says. Each time it divides, the telomere length shortens a bit. When telomere length is too short, cells stop dividing, meaning the body ages. In this study, the researchers measured the length of chromosomal telomeres in the white blood cells of long-distance runners and people who do exercise regularly, and compared them with people of the same age who were healthy and never smoked but exercised very little. The results showed that the former had a slower heart rate and lower blood pressure and cholesterol levels compared to the latter. Not only that, but the former had longer telomere lengths in their leukocyte chromosomes and higher telomerase activity than the latter, which helps maintain telomere length. Study leader Ulrich Laufus, professor of clinical and experimental medicine at Saarland University in Germany, said, “This is direct evidence that exercise has an anti-aging effect.” Cancer prevention and heart protection In the past, it was only recognized that white blood cells had a role in fighting off infections. Later studies have shown that white blood cells have many other uses, such as looking for the growth of abnormal cells such as cancer cells and removing them. One of the reasons cancer rates increase with age is that white blood cells themselves age and can no longer respond effectively to the growth of abnormal cells, says Annabelle Faulgman, a cardiologist at Rush University. If exercise can prevent chromosomal telomeres in white blood cells from becoming shorter, and thus maintain normal white blood cell function, then this could explain why exercise has a cancer-fighting effect. A similar principle applies to heart disease. Aging leukocytes accelerate the accumulation of platelets in response to a number of factors, including high blood pressure. Increased exercise keeps white blood cells “young” and effectively removes platelet buildup. “We know that any form of exercise helps promote cardiovascular health and can prevent cancer,” says Folgman, “and this study explains that from a molecular perspective.” Just the right amount The next question is, how much exercise do people need in order to maintain chromosome telomere length? Does everyone have to turn themselves into a marathoner? Are there hard and fast standards? No one knows the exact answer, says Faulgman. That’s why she suggests it’s best for people to exercise regularly. The intensity of exercise should be adapted to each person’s own conditions. If you have long been accustomed to strenuous exercise, then it is perfectly fine to keep; otherwise, you should stop and not overdo it, so as not to cause harm to the body. Studies have shown that even moderate intensity exercise is good for telomeres. “Not everyone has the potential to be athletic,” Folgman said, “and the safest thing to say is that people need aerobic exercise. But there are many other factors that can affect how a person ages and whether they develop cancer or heart disease.”